xen/CVE-2016-5338-qemut-scsi-esp-OOB-rw-access-while-processing-ESP_FIFO.patch
Charles Arnold 28ce061413 - bsc#983984 - VUL-0: CVE-2016-5338: xen: qemu: scsi: esp: OOB r/w
access while processing ESP_FIFO 
  CVE-2016-5338-qemut-scsi-esp-OOB-rw-access-while-processing-ESP_FIFO.patch
- bsc#982960 - VUL-0: CVE-2016-5238: xen: qemu: scsi: esp: OOB
  write when using non-DMA mode in get_cmd
  CVE-2016-5238-qemut-scsi-esp-OOB-write-when-using-non-DMA-mode-in-get_cmd.patch

- fate#319989 - Update to Xen 4.7 RC5
  xen-4.7.0-testing-src.tar.bz2

- bsc#954872 - script block-dmmd not working as expected - libxl:
  error: libxl_dm.c (another modification)
  block-dmmd

OBS-URL: https://build.opensuse.org/package/show/Virtualization/xen?expand=0&rev=435
2016-06-09 22:06:26 +00:00

66 lines
2.5 KiB
Diff

References: bsc#983984 CVE-2016-5338
The 53C9X Fast SCSI Controller(FSC) comes with internal 16-byte
FIFO buffers. One is used to handle commands and other is for
information transfer. Three control variables 'ti_rptr',
'ti_wptr' and 'ti_size' are used to control r/w access to the
information transfer buffer ti_buf[TI_BUFSZ=16]. In that,
'ti_rptr' is used as read index, where read occurs.
'ti_wptr' is a write index, where write would occur.
'ti_size' indicates total bytes to be read from the buffer.
While reading/writing to this buffer, index could exceed its
size. Add check to avoid OOB r/w access.
Reported-by: Huawei PSIRT <address@hidden>
Reported-by: Li Qiang <address@hidden>
Signed-off-by: Prasad J Pandit <address@hidden>
---
hw/scsi/esp.c | 20 +++++++++-----------
1 file changed, 9 insertions(+), 11 deletions(-)
Update as per:
-> https://lists.gnu.org/archive/html/qemu-devel/2016-06/msg01326.html
Index: xen-4.7.0-testing/tools/qemu-xen-traditional-dir-remote/hw/esp.c
===================================================================
--- xen-4.7.0-testing.orig/tools/qemu-xen-traditional-dir-remote/hw/esp.c
+++ xen-4.7.0-testing/tools/qemu-xen-traditional-dir-remote/hw/esp.c
@@ -435,18 +435,17 @@ static uint32_t esp_mem_readb(void *opaq
DPRINTF("read reg[%d]: 0x%2.2x\n", saddr, s->rregs[saddr]);
switch (saddr) {
case ESP_FIFO:
- if (s->ti_size > 0) {
+ if ((s->rregs[ESP_RSTAT] & STAT_PIO_MASK) == 0) {
+ /* Data out. */
+ ESP_ERROR("PIO data read not implemented\n");
+ s->rregs[ESP_FIFO] = 0;
+ esp_raise_irq(s);
+ } else if (s->ti_rptr < s->ti_wptr) {
s->ti_size--;
- if ((s->rregs[ESP_RSTAT] & STAT_PIO_MASK) == 0) {
- /* Data out. */
- ESP_ERROR("PIO data read not implemented\n");
- s->rregs[ESP_FIFO] = 0;
- } else {
- s->rregs[ESP_FIFO] = s->ti_buf[s->ti_rptr++];
- }
+ s->rregs[ESP_FIFO] = s->ti_buf[s->ti_rptr++];
esp_raise_irq(s);
}
- if (s->ti_size == 0) {
+ if (s->ti_rptr == s->ti_wptr) {
s->ti_rptr = 0;
s->ti_wptr = 0;
}
@@ -482,7 +481,7 @@ static void esp_mem_writeb(void *opaque,
} else {
ESP_ERROR("fifo overrun\n");
}
- } else if (s->ti_size == TI_BUFSZ - 1) {
+ } else if (s->ti_wptr == TI_BUFSZ - 1) {
ESP_ERROR("fifo overrun\n");
} else {
s->ti_size++;